I am a faculty member in computer and cognitive sciences at the University of Toronto. My research explores the interplay of language, cognition, and computation. Natural language relies on a finite vocabulary to express an unbounded array of ideas. I study how the lexicon develops and evolves to convey emerging meanings through time and the extent to which the underlying cognitive processes and representations may be understood in computational terms. In a related line of work, I have been involved with projects that investigate cross-language variation through the lens of communicative efficiency. I also work on the creation of computational tools for exploring the relations of natural language and other domains such as morality.
Lexicon development and evolution
- Yu, L. and Xu, Y. (2025) Infinite mixture chaining: An efficiency-based framework for the dynamic construction of word meaning. Open Mind, 9: 1–24.
- Xu, A., Kemp, C., Frermann, L., and Xu, Y. (2024) Word reuse and combination support efficient communication of emerging concepts. PNAS, 121(46), e2406971121.
- Ramezani, A., Stellar, J.E., Feinberg, M., and Xu, Y. (2024) Evolution of the moral lexicon. Open Mind, 8, 1153-1169.
- Brochhagen, T., Boleda, G., Gualdoni, E., and Xu, Y. (2023) From language development to language evolution: A unified view of human lexical creativity. Science, 381(6656), 431-436.
- Xu, A., Stellar, J.E., and Xu, Y. (2021) Evolution of emotion semantics. Cognition, 217, 104875.
- Sun, Z., Zemel, R., and Xu, Y. (2021) A computational framework for slang generation. TACL, 9, 462-478.
- Ferreira Pinto Jr., R. and Xu, Y. (2021) A computational theory of child overextension. Cognition, 206, 104472.
- Habibi, A.A., Kemp, C., and Xu, Y. (2020) Chaining and the growth of linguistic categories. Cognition, 202, 104323.
- Ramiro, C., Srinivasan, M., Malt, B.C., and Xu, Y. (2018) Algorithms in the historical emergence of word senses. PNAS, 115(10), 2323-2328.
- Xu, Y., Malt, B.C. and Srinivasan, M. (2017) Evolution of word meanings through metaphorical mapping: Systematicity over the past millennium. Cognitive Psychology, 96, 41-53.
Cross-language variation
- Hahn, M. and Xu, Y. (2022) Crosslinguistic word order variation reflects evolutionary pressures of dependency and information locality. PNAS, 119(24), e2122604119.
- Xu, Y., Duong, K., Malt, B.C., Jiang, S., and Srinivasan, M. (2020) Conceptual relations predict colexification across languages. Cognition, 201, 104280.
- Xu, Y., Liu, E., and Regier, T. (2020) Numeral systems across languages support efficient communication: From approximate numerosity to recursion. Open Mind, 4, 57-70.
- Kemp, C., Xu, Y., and Regier, T. (2018) Semantic typology and efficient communication. Annual Review of Linguistics, 4:109-128.
- Xu, Y., Regier, T. and Malt, B.C. (2016) Historical semantic chaining and efficient communication: The case of container names. Cognitive Science, 40(8):2081-2094.
- Ramezani, A. and Xu, Y. (2025) Moral association graph: A cognitive model for automated moral inference. Topics in Cognitive Science, 17, 120-138.
- Ramezani, A., Liu, E., Lee, S.W.S., and Xu, Y. (2024) Quantifying the emergence of moral foundational lexicon in child language development. PNAS Nexus, 3(8), 278.
- Ramezani, A. and Xu, Y. (2023) Knowledge of cultural moral norms in large language models. In ACL.
- Prystawski, B., Grant, E., Nematzadeh, A., Lee, S.W.S., Stevenson, S., and Xu, Y. (2022) The emergence of gender associations in child language development. Cognitive Science, 46, e13146.
- Xie, J.Y., Ferreira Pinto Jr., R., Hirst, G., and Xu, Y. (2019) Text-based inference of moral sentiment change. In EMNLP-IJCNLP, 4654-4663, Hong Kong, China.
